The invention discloses a large-
diameter counter bit
machining method and relates to a counter bit
machining method. By means of the large-
diameter counter bit
machining method, the problems that by means of an existing large-
diameter counter bit machining method, tool materials are wasted, the machining allowance is extremely large, and
machining time is wasted are solved. The large-diameter counter bit machining method comprises the steps that 1, a counter bit and a tool bar are turned through a lathe; 2, a counter bit groove, a front corner and a rear corner are milled through a horizontalmilling
machine; 3, a tool bar flat
tail is milled through the horizontal milling
machine, and a tool bar
kidney-shaped hole is milled; 4, a bench worker drills a vent hole communicating with a conical hole in the tool bar; 5, the counter bit and the tool bar are welded into a whole through electrowelding, and after
welding, the
welding stress is removed; 6, heat treatment is conducted on a 90-degree
cutting conical surface, machined in step 1, of the counter bit till HRC66-68 is reached; 7, central holes in the two ends of the counter bit are ground; 8, the 5-degree front corner of the counter bit is ground through a tool
grinding machine; 9, the central holes in the two ends of the counter bit are jacked through two jacking tips, the 90-degree
cutting conical surface of the counter bit is ground, and a Mohs 5 taper-shank is ground; and 10, the 10-degree counter bit rear corner is ground through the tool
grinding machine.